Study registration: *
Publication Ranzani OT, medRxiv, 2021
Dates: 2021-06-25 to 2021-09-30
Funding: Mixed (JC is supported by the Oswaldo Cruz Foundation (Edital Covid-19 – resposta rápida: 48111668950485). OTR is funded by a Sara Borrell fellowship (CD19/00110) from the Instituto de Salud Carlos III. OTR acknowledges support from the Spanish Ministry of Science and Innovation through the Centro de Excelencia Severo Ochoa 2019-2023 Program and from the Generalitat de Catalunya through the CERCA Program.)
Conflict of interest: Yes (Dr Croda reported receiving grants from the NIH and Sanofi during the conduct of the study and personal fees from Pan American Health Organization outside the submitted work. No other disclosures were reported.)

Methods

Study design:Test-negative
Description of participants: RT-PCR from adults residing in Mato-Grosso do Sul
Inclusion criteria:
  • "adults with an RT-PCR residing in Mato-Grosso do Sul, collected within 10 days of symptoms onset"

Exclusion criteria:
  • "previous infected individuals"

Follow-up duration (months): 3
Vaccines:
  • 1 dose of Ad26.COV2.S
Variant description :
Variant name: Delta
Evidence: Indirect evidence (prevalence of variant in the population: 1 to 99%)
Documents
available

Protocol

NR

Statistical plan

NR

Data-sharing stated: NR
Data accessibility: NR
General comment Some concerns over uncontrolled confounding; in addition there are uncertainties over the possibility of selection bias in a test-negative design and in relation to missing data.